Let-off means for looms



Aug. 11, 1925.

1,548,995 W. HARRIS LET-OFF MEANS FOR LQOMS Original Filed Dec. 14. 1925WITNESS TTKG,

A TTORIVEY Patented Aug. 11, 1925.

UNITE ST'E'ES WILLIAM HARRIS, OF PATERSQN, NEW JERSEY.

LET-OFF MEANS FOR LOOMS.

Ap lication filed December 14, 1923, Serial No. 680,601. Renewed March7, 1925.

To all whom 2'25 may concern Be it known that I, NumIAM Haunts, acitizen of the United States, residing at Paterson, in the county ofPassaic and State of New Jersey, have invented certain new and usefulImprovements in Let-Off Means for Looms, of which the following is aspecification. y

In let-oft mechanisms for looms of the kind'in which. slip-friction isresorted to to ,control the rotation of the warp-beam (characterizedusually by a rope wound around the beam head and carrying weights at itsends, the forward or lighter weight being adapted to contact with thefloor at intervals to cause relaxation of the rope) there is thetendency for the beam to turn under the pull of the warp in a jerkyfashion, due when analyzed to the braking element alternately adheringto the beam and allowing it to slip, and this tendency becomes an activefactor in producing faulty fabrics in respects into which it isunnecessary to go in detail in this specification, since, this type oflet-off mechanism being the one most commonly used, they are well knownto those skilled in the art of weaving. Suffice it to say that manyexpedients have in practice been resorted to to alleviate thetroublesome conditions that obtain when slip-friction is relied on toafford resistance to the rotation of the beam whereby to maintain theproper tension on the warp, none of which fully accomplishes theprincipal object under all the different conditions that prevail inpractical weaving and most of which encumber the loom and require suchskill and attention to obtain the best results as exceed the capacity ofthe ordinary loom attendant.

Instead of using slip-friction, which is responsible as stated for jerkyrotary delivery movements of the beam, I arrange in permanent tractiveengagement with a part of a rotary means to supply the warp a flexibleattenuated device which extends from said part relatively reversely tothe direction in which the warp extends from the beam or other elementof said means on which it is wound and is connected to a paying-outmeans confined to move in synchrony with means (as the takeup of theloom) for exerting a pull on the warp, said connection being tensioned.

By this system the resistance to the rotation of the beam and hence tothe advance of the warp is constantly present, sudden release-impulsesthereof never ensuing, and a consequence no faults can occur in theweaving such as those attributable to let-oft mechanisms employingslip-friction as a medium of resistance to the delivery movements of thebeam, and no special skill is required either to establish or tomaintain the system in proper working order at all times and under allthe different and varying conditions that are incident to weaving.

In the drawings,

Fig. 1 is a side elevation of a loom embodying my invention; and

Fig. 2 is a sectional view on the line 2-2, Fig. 1.

A supporting means is afforded by the loom frame a which has the usualmeans, as the breast-beam b and a roller 0, over which the warp A(having interwoven with it the weft or filling and so as to its forwardportion being a part of the fabric B) is extended as usual. At the frontof the loom is arranged a take-up mechanism of any usual form, the samebeing here represented by a sand roller. d and a cloth-beam e on whichto wind up the part of the warp with which the weft or filling has beenincorporated to form the fabric, the latter being maintained in a bendaround the sand roller by two other rollers 7, as usual. The sand rolleris kept from backward rotation by any suitable means, here shown as aholding paw d engaging a ratchet d fixed to r0- tate with the sandroller. It is not material to the present invention in what manner orwhat means the sand roller and beam e are rotated to advance and Wind upthe fabric.

At the rear of the loom is journaled the warp beam 9. It has fixed onthe end of one of its gudgeons h a double-flanged head which is arrangedoutward of the loom frame in the present case.

7' is the aforementioned attenuated flexible device (which may be a ropeor chain) and Z2 Z: guides in engagement with which said device extends,the guides being here two peripherally grooved pulleys journaled in theupper part of the loom frame and projecting laterally therefrom.

The rearward end of the device is secured to the periphery of the headcl between its flanges, being wound more or less thereon in thedirection reverse to the winding thereon of the warp.

The mentioned tensioning is obtained by means here in the form of aweight, being shown as comprising the carrier 0 having a pulley engagedin a bight or bend y" of device j between pulleys 7 and carrying one ormore weights 9.

A double-flanged head 1 is shown fixed on the end of the sand rollershaft and having the other or forward end of the device wound thereonreversely to the direction in which the fabric extends around the sandroller. Therefore the device is continually and automatically paid outat one end while, during advance of the sheet of warp and fabric, itiswound up at the other, the tension means being active to exert a pull onboth end portions of the warp. A bend such as j in the device j is notindispensable because as fast as said device is on the one hand taken upit is on the other hand paid out, unless, of course, (as in the caseillustrated by the drawings) the winding up at 2' and the unwinding at rinvolve change of the wound mass in respect to diameter, when such abend will be necessary to afford compeusation for the difference in therates of advance of the two end portions of the device then exiting. llhen the device becomes fully paid out from head r it may be uncoiledfrom head 7r having removed the weights) and recoiled on head r.

The means (Z may be regarded as means to exert a pull on the warp andthe means r as a paying-out means confined to move in synchrony with thepaying-out means and adapted to pay out said device when the first-namedmeans is exerting a pull on the warp.

h loreover, while generally it will perhaps be best to apply thetensioning force so that it acts on a device such as j transverselythereof the invention is not correspondingly limited. Any tensioningconnection as jg) connecting the paying-out means and a part of therotary warp-supply means and having a portion thereof in permanent tractive engagement with said part and extending therefrom relativelyre-versely to the direction in which the warp extends from the elementon which it is wound and being adapted to be paid. out by the paying-outmeans when the means to exert a pull on the warp is exerting such pullis to be regarded as falling within the scope of this invention. By theterm permanent tractive engagement as herein used I mean a tractiveengagement not permitting slippage.

Having thus fully described my invention, what I claim as new and desireto secure by Letters Patent is:

1. In a loom, the combination of a support, rotary means to supply thewarp journaled in said support and including a rotary element on whichthe warp is wound, means to exert a pull on the warp and thereby unwindit from said element, causing rotation of the first means, a paying-outmeans con lined to move in synchrony with the second amed meansindependently of the warp, and a flexible tensioning connectionconnecting said paying-out means and a part of said rotary means andhaving a portion thereof in permanent tractive engagement with said partand extending therefrom relatively reversely to the direction in whichthe warp extends from said element and said connection being adapted tobe paid out by the paying-out means when the second-named means isexerting a pull on the warp.

2. In a loom, the combination of a support, rotary means to supply thewarp journaled in said support and including a rotary element on whichthe warp is wound, means to exert a pull on the warp and thereby unwindit from said element, causing rotation of the first means, a rotarypayingout member confined to rotate in synchrony with the second-namedmeans, and a flexible tensioning connection connecting said 1nember anda part of said rotary means and hav-- ing a portion thereof in permanenttractivc engagement with said part and extending therefrom relativelyreversely to the direc tion in which the warp extends from said elementand another portion thereof connected to said member and adapted to bepaid out thereby when the second-named means is exerting a pull on thewarp.

3. In a loom, the combination of a support, rotary means to supply thewarp journaled in said support and including a rotary element on whichthe warp is wound, means to exert a pull on the warp and thereby unwindit from said element, causing rotation of the first means, a paying-outmeans confined to move in synchrony with the secondnamed meansindependently of the Warp, a flexible attenuated device connected withand adapted. to be paid out by the payingout means when the second-namedmeans is exerting a pull on the warp and having a portion thereofarranged in permanent tractive engagen'lent with a part of said ro tarymeans and extending therefrom relatively r-evei'sely to the direction inwhich the warp extends from said element, and tension means acting onsaid device transversely thereof.

4. In a loom, the combination of a support, rotary means to supply thewarp journaled in said support and including a rotary element on whichthe warp is wound, means to exert a pull on the warp and thereby unwindit from said element, causing rotation of the first means, a rotarypaying-out meinber confined to rotate in synchrony with the second-namedmeans, a flexible atenuated device having a portion thereof in permanenttractive engagement with a part of said rotary means and extendingtherefrom relatively reversely to the direction in which the warpextends from said element and another portion thereof arranged inpermanent tractive engagement withsaid member and arranged to be paidout thereby when the second-named means is exerting a pull on the warp,and tension means acting on said device transversely thereof.

5. In a loom, the combination of a sup port, rotary means to supply thewarp journaled in said support and including a rotary element on whichthe warp is wound, means to exert a pull on the warp and thereby un-Wind it from said element, causing rotation of the first means, a rotarypaying-out means confined to rotate in synchrony with the sec ond-namedmeans, and a tensioning connection in permanent tractive engagement witha part of the first means and a part of the paying-out means andimparting force to rotate the former part relatively contrary to thepull of the warp and to rotate the latter part in relatively the samedirection as the warp is pulled.

In testimony whereof I afiix my signature.

WILLIAM HARRIS.

